Sprinkler base



FIG. 1 is a top perspective view of a sprinkler base showing my new design;

FIG. 2 is a bottom perspective view thereof;

FIG. 3 is a side elevational view thereof, the opposite side being identical;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof; and,

FIG. 6 is a front elevational view thereof, the rear view being identical. 

The ornamental design for a sprinkler base design, as shown and described. 